1. (a) Field of the Invention
The present invention relates to an apparatus, a method, and a sensor for scanning states of engine oil of a vehicle. According to the exemplary embodiments of the present invention, physical properties, chemical properties, and a quantity of engine oil are measured by respective sensors or a complex sensor, and then the quality of engine oil is determined by comparing a measured value of properties of engine oil with a predetermined value according to driving conditions or driving history information, and is expressed on the instrument panel such that the driver can notice whether it can be further used. In addition, exchange history, consumed quantity, and information of oxidization history of the engine oil are provided to the system scanner.
2. (b) Description of the Related Art
Since engine oil may include various materials and additives, and may be made in various manufacturing processes, the engine oil may have physical and chemical diversities and its quality may be variously changed according to the degree of oxidation, the condition of the engine, the kind of fuel used, driving conditions, and environmental conditions. Therefore, an apparatus or a system for scanning and monitoring engine oil should accurately and efficiently measure diverse qualities of the engine oil, and should indicate current condition, refill timing, and exchange timing of the engine oil.
Generally, engine oil functions to reduce friction, to cool down the engine, to disperse weight, to seal, to clean, and to prevent rust. However, as the engine oil is used, the above-mentioned functions become less effective. Since engine oil is used under high temperature in the combustion chamber, engine oil becomes oxidized and materials generated by combustion are contained in the engine oil. In addition, fuel like gasoline or diesel leaking at the injector may dilute engine oil, and metal fragments due to abrasion of frictional parts of the engine may be precipitated or float in the engine oil. In addition, when a problem occurs in the engine, antifreeze solution or water can flow into the engine oil through a connecting part (for example a gasket) of the engine.
Generally, under normal conditions when there is no problem in the engine, as the age of the engine oil becomes longer, the viscosity of the engine oil increases. Therefore, during the driving, the increased viscosity of the engine oil may problematically create excessive friction loss.
However, in the case that fuel has leaked through the injector or water increases in the engine oil, as the engine is operated, the viscosity of the engine oil decreases. Then, excessive abrasion may occur at the frictional parts of the engine. Therefore, the viscosity is one of the important physical properties of engine oil and should be measured accurately.
Conventional apparatus for measuring physical properties of engine oil use a method for merely measuring electrical capacity of the coil installed in a sensor, or measuring electrical capacity by a sensor having a network structure made by semiconductor processing. Therefore, it is difficult to correctly measure the viscosity of the engine oil. It is also difficult to measure chemical properties of the engine oil by measuring electrical capacity and to secure durability of the sensor, because metal fragments contained in the engine oil become attached to the sensor.
A conventional method for measuring the level of engine oil is a manual method that uses the naked eye with an installed oil level gauge. However, such a method is very inconvenient, and it is impossible to measure oil level when driving.
Generally, a pressure drop warning lamp installed in an instrument panel is lit when the oil level is below an oil pump pickup tube. When the oil pressure is much lower than the general pressure of 5 atm, for example lower than 0.5 atm, the pressure drop warning lamp is operated. However, even if the driver stops operation of the engine as soon the pressure drop warning lamp is seen, the engine may have already incurred serious damage. Even if it is very short time, the frictional parts of the engine can be seriously damaged, and the damage cannot be reversed by refilling the engine oil. Therefore, it is important to provide an oil level sensor by which monitoring the level of engine oil is always possible.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.